1. Field of the Invention
The present invention relates to plumbing products and in particular to water saving toilet designs.
2. Description of Related Art
The need for water conservation is widely recognized and has become an issue to many consumers. Limited resources, drought, water pollution, and rising populations have led to water shortages in many areas of the world. The problem has been recognized to the extent that many communities place regulations on the use of water and even impose fines when limits on water use are exceeded. Some cities are now recycling waste water back into the fresh water supply while other cities have been forced to limit their growth due to lack of fresh water and over use demands on insufficient wastewater treatment facilities.
The toilet is a water-using appliance so common that on average each household has more than one of them. According to the American Water Works Association Research Foundation, the largest daily user of water in the average home is the toilet, at 26.7% of the daily water used per home. This amount exceeds the shower at 16.8% and the washing machine at 21.7%. Calculating amounts from a standard toilet that uses 3.5 gallons of water per flush, one person can consume as much as 19.5 gallons per day, or 7,135 gallons per year. Newer low flow toilets use only 1.6 gallons of water per flush. However, even with a low flow toilet one person can even still use up to 10 gallons per day, due to propensity for individuals to flush these types of toilets more than once per use. The newest low flow toilets, while still using 1.6 gallons per flush, are much more efficient at removing solid wastes, and accordingly show a drop in double flushes. These toilets typically use less than 10 gallons per day. Even given these improved low flow toilets, there is room for improvement and it is well understood that more efficient toilet flush systems could save even more water beyond that already saved by current “low flow” toilets.
Because the above-recognized need to conserve water has created a market for new and improved low flow toilets, the prior art is thus plentiful and embodies many attempts by individuals and organizations to create ways to maximize the efficiency of the toilet flush system. Nearly all of the prior art attempts to address the problem through means to limit the amount of water used by each individual flush, either through early termination of the flush cycle, increased velocity of a smaller amount of water, or even dual flush systems utilizing two valves located at different levels within the toilet tank. See U.S. Pat. No. 6,510,563 to Jarosiinski et al, U.S. Pat. No. 4,485,501 to Kloner and U.S. Pat. No. 5,511,253 to Zamudio-Castillo et al. Some systems require the user to hold the valve open for as long as is necessary to complete the flush, such as in U.S. Pat. No. 5,129,110 to Richter.
The above systems are limited in that they only attempt to regulate the water use of a single flush, rather than creating a system wherein at least one flush per use is not always necessary. In addition, many of the prior art systems are very complex such that the reliability of the systems are questionable. Cost and difficulty of installation are further barriers to popularity and wide spread use of such systems. Finally, as mentioned above, many prior art systems require the use of the same amount of water for every flush, regardless of what is being flushed, thereby resulting in many flushes using too much water, while some other flushes use too little.
To overcome the limitations of the above prior art, non-flush liquid only toilets have been developed. These toilets are common in state parks and other outdoor areas where access to water is limited. While these systems can use zero water simply because the mere presence of gravity causes liquid waste to drain, they generally are malodorous if not properly maintained with an oil based cleaner. One common material used in toilet construction, porcelain, retains some liquid waste even after the majority has drained away. Thus, such systems would not be acceptable for common household use.
In order to overcome the limitations and problems inherent with the prior art toilet systems it is a first objective of the present invention to provide an improved toilet which is simple, efficient, low-flow solution which does not require a flush cycle after every toilet use.
It is a further objective of the present invention to provide an improved toilet with separate pathways for liquid and solid waste.
It is a further objective of the present invention to prevent overuse of water for flushing of liquid waste while preventing underuse of water for flushing of solid waste.
It is a further objective of the present invention to provide an improved toilet which both fits and works with existing plumbing structures and hardware.
Finally, it is a still further objective of the present invention to provide an improved toilet that is acceptable to the public due to its simplicity, reliability, and user friendliness.